Yamaha YZF-R125 Owners Manual: Motorcycle care and storage

Troubleshooting charts

Starting problems or poor engine performance Starting problems or poor engine performance Engine overheating WARNING Do not remove the radiator cap when the engine and radiator are hot. S ...

Matte color caution

NOTICE Some models are equipped with matte colored finished parts. Be sure to consult a Yamaha dealer for advice on what products to use before cleaning the vehicle. Using a brush, harsh ch ...

Other materials:

Throttle position sensor
1. Check: Throttle position sensor a. Connect the digital circuit tester to the terminals of the throttle body sensor assembly coupler as shown. Positive tester probe → gray/red terminal "1" Negative tester probe → gray/black terminal "2" b. Measure the throttle pos ...

Checking the valve seats
The following procedure applies to all of the valves and valve seats. 1. Eliminate: Carbon deposits (from the valve face and valve seat) 2. Check: Valve seat Pitting/wear Replace the cylinder head. 3. Measure: Valve seat width C "a" Out of specification Replace the ...

Checking the clutch springs
The following procedure applies to all of the clutch springs. 1. Check: Clutch spring Damage Replace the clutch springs as a set. 2. Measure: Clutch spring free length "a" Out of specification Replace the clutch springs as a set. ...